Filtering Hack Attempts Via Http Auth

Is there a way I can filter attempts to hack via http auth? I'm getting http auth requests which are trying to use SQL Injection with the login/username.

It's not getting anywhere but I would like to stop the request before it reaches the application if possible? I tried using SecFilter but that doesn't seem to stop it (I assume that it's just looking at the actual request string rather than the http auth details)

EDIT: Apologies, feel free to move this in to general. I didn't mean to put this in Features/Feedback